The present invention relates to a process for the production of piperidine derivatives with microorganisms.
Terfenadine, 1-(p-tert-butylphenyl)-4-[4xe2x80x2-(xcex1-hydroxydiphenylmethyl)-1xe2x80x2-piperidinyl]-butanol is a non-sedating anti-histamine. It is reported to be a specific H1-receptor antagonist that is also devoid of any anticholingeric, anti-serotoninergic, and anti-adrenergic effects both in vitro and in vivo. See D. McTavish, K. L. Goa, M. Ferrill, Drugs, 1990, 39, 552; C. R. Kingsolving, N. L. Monroe, A. A. Carr, Pharmacologist, 1973, 15, 221; J. K. Woodward, N. L. Munro, Arzneim-Forsch, 1982, 32, 1154; K. V. Mann, K. J. Tietze, Clin. Pharm. 1989, 6, 331. A great deal of effort has been made investigating structure-activity relationships of terfenadine analogs, and this is reflected in the large number of U.S. patents disclosing this compound and related structures as follows:
U.S. Pat. No. 3,687,956 to Zivkovic
U.S. Pat. No. 3,806,526 to Carr, et. al.
U.S. Pat. No. 3,829,433 to Carr, et. al.
U.S. Pat. No. 3,862,173 to Carr, et. al.
U.S. Pat. No. 3,878,217 to Carr, et. al.
U.S. Pat. No. 3,922,276 to Duncan, et. al.
U.S. Pat. No. 3,931,197 to Carr, et. al.
U.S. Pat. No. 3,941,795 to Carr, et. al.
U.S. Pat. No. 3,946,022 to Carr, et. al.
U.S. Pat. No. 3,956,296 to Duncan, et. al.
U.S. Pat. No. 3,965,257 to Carr, et. al.
U.S. Pat. No. 4,742,175 to Fawcett, et. al.
In animal and human metabolic studies, terfenadine has been shown to undergo extensive hepatic first-pass metabolism, and, after usual dosages it cannot be detected in plasma unless very sensitive assays are used. A specific hepatic cytochrome P-450 enzyme converts terfenadine to the major metabolite 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1-xcex1-dimethylphenylacetic acid, also known as terfenadine carboxylic acid metabolite. This metabolite can be readily detected in plasma and is considered to be the active form of orally administered terfenadine.
Side effects reported with terfenadine are cardiac arrhythmias (ventricular tachyarrhythmias, torsades de points, ventricular fibrillation), sedation, GI distress, dry mouth, constipation and/or diarrhea. The most serious of these, and potentially life threatening, are cardiac arrhythmias, which are related to terfenadine""s ability to prolong the cardiac QT interval, and are only reported in patients administered terfenadine with liver disease or who also take the antifungal drug ketoconazole or the antibiotic erythromycin.
Since cardiac side effects of terfenadine have been reported in patients with impaired liver function, as well as in patients also taking antibiotics known to suppress hepatic enzyme function, it was speculated that the cardiac side effects were due to accumulation of terfenadine and not due to accumulation of terfenadine carboxylic acid metabolite. Patch clamp studies in isolated feline ventricular myocytes support the contention that terfenadine, and not the carboxylic acid metabolite, is responsible for cardiac side effects. At a concentration of 1 xcexcM, terfenadine caused a greater than 90% inhibition of the delayed rectifier potassium current. At concentrations up to 5 xcexcM, the terfenadine carboxylic acid metabolite had no significant effect on the potassium current in this assay (See R. L. Woosley, Y. Chen, J. P. Frieman, and R. A. Gillis, JAMA 1993, 269, 1532). Since inhibition of ion transport has been linked to cardiac abnormalities, such as, arrhythmias, these results indicate that terfenadine carboxylic acid is likely not liable to cause cardiac arrhythmias, at dose levels at which there is a distinct risk of such a side effect being caused by terfenadine itself.
Carebastine, 4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-oxobutyl]-xcex1,xcex1-dimethylphenylacetic acid, is the carboxylic acid metabolite of ebastine, 1-(p-tert-butylphenyl)-4-[4xe2x80x2-(xcex1-diphenylmethoxy)-1xe2x80x2-piperidinyl]-butanol. Both compounds possess potent selective histamine H1-receptor blocking and calcium antagonist properties and should prove useful in the treatment of a variety of respiratory, allergic, and cardiovascular disease states.
These compounds relax bronchial and vascular smooth muscle in vitro and in vivo and inhibit the constrictor influence of noradrenaline, potassium ions, and various other agonist drugs. The compounds also inhibit responses of intestinal and tracheal preparations to histamine, acetylcholine, and barium chloride and block the bronchoconstriction induced by histamine aerosol in guinea pigs in doses less than 1 mg/kg animal body weight administered orally. They also possess antianaphylactin properties in the rat, inhibit the skin lesions to a variety of anaphylactic mediators (histamine, 5-hydroxytryptamine, bradykinin, LCD4, etc.), and antagonize the Schultz-Dale response in the sensitive guinea-pig.
Piperidine derivatives related to the terfenadine carboxylic acid metabolite are disclosed in the following U.S. patents:
U.S. Pat. No. 4,254,129 to Carr, et. al.
U.S. Pat. No. 4,254,130 to Carr, et. al.
U.S. Pat. No. 4,285,957 to Carr, et. al.
U.S. Pat. No. 4,285,958 to Carr, et. al.
In these patents, 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetic acid and related compounds are prepared by alkylation of a substituted piperidine derivative of the formula: 
with an xcex1-haloalkyl substituted phenyl ketone of the formula: 
wherein the substituents halo, R1, R2, n, Z, and R6 are described in column 6 of U.S. Pat. No. 4,254,130.
In similar fashion, U.S. Pat. No. 4,550,116 to Soto et al. describes preparation of piperidine derivatives related to carebastine by reacting the xcex1-haloalkyl substituted phenyl ketone with a substituted hydroxypiperidine derivative of the formula: 
U.S. Pat. No. 4,254,130 indicates that xcex1-haloalkyl substituted phenyl ketones, wherein Z is hydrogen, are prepared by reacting an appropriate straight or branched lower alkyl C1-6 ester of xcex1,xcex1-dimethylphenylacetic acid with a compound of the following formula: 
under the general conditions of a Friedel-Crafts acylation, wherein halo and m are described in column 11 of U.S. Pat. No. 4,254,129. The reaction is carried out in carbon disulfide as the preferred solvent.
Other procedures for synthetically producing terfenadine carboxylic acid metabolite are disclosed in U.S. Pat. Nos. 5,578,610, 5,581,011, 5,589,487, 5,663,412, 5,750,703 and 5,994,549, as well as PCT Application Nos. WO95/00492, WO94/03170, and WO95/00480.
Another approach to producing terfenadine carboxylic acid metabolite-like compounds involves the conversion of terfenadine-like compounds using fungi. This procedure is disclosed in U.S. Pat. No. 5,204,249 to Schwartz et. al. and U.S. Pat. No. 5,990,127 to Meiwes et. al. In the Schwartz patent, fungi from the genus Cunninghamella are used to convert ebastine to carebastine. The Meiwes patent employs fungi species from the genera Cunninghamella and Absidia to transform terfenadine to its acid metabolite. Although these procedures have been found to be useful in producing terfenadine carboxylic acid metabolite-like compounds, the initial yield of these products from such process is quite low and the restriction to filamentous fungi, from these genera previously identified, creates undesirable limitations for a commercially viable process.
The present invention is directed toward an improved process for preparation of terfenadine carboxylic acid metabolite and carebastine derivatives using microbial catalysts.
The present invention relates to the production of a product compound having the Formulae IA and/or IB: 
wherein
n is 0 or 1;
R1 is hydrogen or hydroxy;
R2 is hydrogen;
or, when n is 0, R1 and R2 taken together form a second bond between the carbon atoms bearing R1 and R2, provided that when n is 1, R1 and R2 are each hydrogen;
R3 is xe2x80x94COOH or xe2x80x94COOR4;
R4 is an alkyl or aryl moiety;
A, B, and D are the substituents of their rings, each of which may be different or the same, and are selected from the group consisting of hydrogen, halogens, alkyl, hydroxy, and alkoxy.
This process involves incubating a starting compound having the Formulae IIA and/or IIB: 
wherein R3* is xe2x80x94CH3 and R1, R2, A, B, and D are defined above.
in the presence of a microorganism under conditions effective to produce the product compound. The microorganism can be from the genus Streptomyces, Stemphylium, Gliocladium, Bacillus, Botrytis, Cyathus, Rhizopus, Pycniodosphora, Pseudomonas, Helicostylum, Aspergillus, Mucor, Gelasinospora, Rhodotorula, Candida, Mycobacterium, or Penicillium.
The present invention also relates to the production of a product compound having a structure according to Formulae IA and/or IB by incubating a starting compound having a structure according for Formulae IIA and/or IIB in the presence of Cunninghamella bainieri under conditions effective to produce the product compound.
The present invention provides an alternative and/or improved process for the preparation of carboxyterfenadine from terfenadine. The selectivity and yields of carboxyterfenadine obtained using the strains and processes according to the present invention can be higher than those obtained using known strains. In addition, the identification of many strains, especially bacterial strains (both gram positive and gram negative), for the target conversion, can permit significant strain improvement, processing, and manufacturing advantages over previously used filamentous fungal strains.
Importantly, and surprisingly, Streptomyces, Bacillus, and Pseudomonas represent gram positive and gram negative eubacterial strains, an entirely different kingdom from the filamentous fungi previously identified to perform the target transformation. Techniques for strain improvement and genetic manipulation of bacterial strains, including especially Streptomyces, Bacillus, and Pseudomonas species, are considerably simpler and better established compared with fungi, such as Cunninghamella strains. Moreover, commercial-scale processing of non-filamentous microorganisms, including non-filamentous fungi, yeasts, and eubacteria, provides many additional and more economical fermenter and purification processes than are feasible for filamentous fungi alone.
Moreover, the variety of microbial biocatalysts allow for the transformation to a broad variety of structural variations. In addition, the identification of multiple strains possessing genes and enzymes useful for such transformation is an important prerequisite to the use of modern molecular biological techniques for the further optimization of microorganisms as industrial catalysts for the production of piperidine derivatives.
The present invention relates to the production of a product compound having a structure according to Formulae IA and/or IB: 
wherein
n is 0 or 1;
R1 is hydrogen or hydroxy;
R2 is hydrogen;
or, when n is 0, R1 and R2 taken together form a second bond between the carbon atoms bearing R1 and R2, provided that when n is 1, R1 and R2 are each hydrogen;
R3 is xe2x80x94COOH or xe2x80x94COOR4;
R4 is an alkyl or aryl moiety;
A, B, and D are the substituents of their rings, each of which may be different or the same, and are selected from the group consisting of hydrogen, halogens, alkyl, hydroxy, and alkoxy.
This process involves incubating a starting compound having a structure according to Formulae IIA and/or IIB: 
wherein R3* is xe2x80x94CH3 and R1, R2, A, B, and D are defined above, in the presence of a microorganism under conditions effective to produce the product compound. The microorganism can be from the genus Streptomyces, Stemphylium, Gliocladium, Bacillus, Botrytis, Cyathus, Rhizopus, Pycniodosphora, Pseudomonas, Helicostylum, Aspergillus, Mucor, Gelasinospora, Rhodotorula, Candida, Mycobacterium, or Pennicillium.
The present invention also relates to the production of a product compound having a structure according to Formulae IA and/or IB by incubating a starting compound having a structure according to Formulae IIA and/or IIB in the presence of Cunninghamella bainieri under conditions effective to produce the product compound.
The process of the present invention is carried out in a liquid growth medium. What constitutes an appropriate growth medium is dependent on the specific microorganism and purpose, as is familiar to those trained in the art. In general, the growth medium contains carbon sources, such as dextrose, sucrose, citrate, and/or starch, and nitrogen sources, such as soybean flour, yeast extract, tryptone, malt extract, and/or ammonium acetate. In addition, the growth media contains inorganic salts, such as sodium phosphate, potassium phosphate, sodium chloride, calcium chloride, calcium sulfate, calcium carbonate, and/or magnesium sulfate, and trace elements, such as iron, zinc, copper, molybdenum, manganese, or other metal salts.
The microorganisms used in the present invention can be selected from the following genera: Streptomyces, Stemphylium, Gliocladium, Bacillus, Botrytis, Cyathus, Rhizopus, Pycniodosphora, Pseudomonas, Helicostylum, Aspergillus, Mucor, Gelasinospora, Rhodotorula, Candida, Mycobacterium, or Pennicillium. For the genus Streptomyces, suitable species include Streptomyces catenulae, Streptomyces cavourensis, Streptomyces rimosus, and Streptomyces griseus. For the genus Stemphylium, Stemphylium consortiale is a suitable species. Useful Aspergillus species include Aspergillus aliaceus, Aspergillus carbonarium (Bainier) Thom, Aspergillus flavipes, Aspergillus fumigatus, Aspergillus ochraceous, and Aspergillus terricola. As to the genus Gliocladium, the species Gliocladium deliquescens is particularly useful. With regard to the Bacillus genus, the species Bacillus cereus, Bacillus subtilis, and Bacillus fusiformis can be used to carry out the process of the present invention. A suitable species of Botrytis is Botrytis allii. As to the genus Cyathus, the species Cyathus striatus can be used. Rhizopus oryzae is a representative member of the Rhizopus genus which can be used to carry out the present invention. Useful Pseudomonas species include Pseudomonas putida. With regard to the Pycniodosphora genus, the species Pycniodosphora dispersa can be used. For the Helicostylum genus, the species Helicostylum piriforme can be used to carry out the process of the present invention. As to the Mucor genus, the species Mucor circinelloides f. griseo-cyanus, Mucor recurvatus, and Mucor mucedo can be used to carry out the present invention. The species Gelasionospora autosteria is a member of the Gelasionospora genus which is suitable for carrying out the process of the present invention. With respect to the genus Rhodotorula, the species Rhodotorula rubra can be used. For the genus Pennicillium, the species Penicillium notatum and Pennicillium chyrsogenum can be used to practice the process of the present invention. With regard to the Candida genus, the species Candida guilliermondii, Candida lipolytica, and Candida parasilosis var. quercus can be utilized. Suitable Mycobacterium species include Mycobacterium bisrymcum. 
For each strain, the invention relates to the use of the whole microorganism, and components thereof, including, but not limited to, cell extracts, microsomes, isolated enzymes, and genes, for the chemo- and regioselective oxidation of Formulae IIA and/or IIB to products of Formulae IA and/or IB.
Furthermore, mutants and selectants of the microbes of the listed genera and especially those of the specific strains described herein, are also suitable for use in the process of the present invention. Mutants can be created by classical methods of mutagenesis for strain improvement, such as random mutagenesis mediated by chemicals or electromagnetic waves, or by modern methods for genetic manipulation, such as error prone PCR, codon mutagenesis, or gene shuffling.
Another aspect of the present invention relates to the use of the species Cunninghamella bainieri in carrying out the process of the present invention.
The present invention also relates to the discovery and use of microorganisms of the genera Streptomyces, Gliocladium, and Stemphyllium to perform as superior agents for the selective oxidation of terfenadine (Formulae IIA/IIB) to carboxyterfenadine (Formulae IA/IB) compared with fungi of the genera Cunninghamella and Absidia.
Additionally, microbial strains of the genera Botrytis, Rhizopus, Cyathus, Bacillus, Pycniodosphora, Pseudomonas, Helicostylum, Aspergillus, Gelasinospora, Rhodotorula, Penicillium, and Candida have also been identified as oxidizing terfenadine to carboxyterfenadine in yields greater than 3% without optimization. In prior experimentation, Meiwes et al. identified only two strains that produced yields of 3% or greater during initial screening.
Moreover, microorganisms from the genera Ascoidia, Enterococcus, Fusidium, Lentinus, Lophotrichus, Mycobacterium, Polyporus, Spicaria, and Trichophyton have been found to be biocatalysts capable of oxidizing terfenadine to carboxyterfenadine.
All of these microorganisms are freely available from public culture collections. The specific identity and source of microbial cultures are described in the examples below.
Microbial cultures used for the present invention can be maintained according to procedures well known to those skilled in the art, such as on solid media, preserved in mineral oil and lyophilized or frozen.
Microbial cultures can be maintained on an appropriate solid media, such as 30 grams/liter of sabouraud dextrose broth and 20 grams/liter of agar. Preferably, for some strains, preparation of inocula including a low temperature cryopreservation and thawing technique (i.e. the xe2x80x9cCryoreadyxe2x80x9d technique) serves to improve the approach for transforming the starting material to the piperidine product of the present invention by reducing the time required for producing suitable inocula and raising production of the piperidine product. After growing the culture in an appropriate liquid medium, the microbial suspension is centrifuged, the spent liquid medium is removed, and the concentrated cell pellet is resuspended with an equal volume of sterile 20% glycerol stock and fresh broth, to produce a cell suspension in 10% glycerol.
From solid media, the microorganisms are initially propagated through one or more stages in a neutral liquid culture medium appropriate to support the growth of specific strains (i.e. the xe2x80x9cMultistagexe2x80x9d procedure). Typical media for initial propagation consists of 20 g/l of glucose, 5 g/l of yeast extract, 5 g/l of soybean flour, 5 g/l of NaCl, and 5 g/l of K2 HPO4. The initial stage of microbial cultures was incubated at 29xc2x0 C. and 250 rpm for 48 or 72 hrs. Subsequent stages were inoculated, with a heavy inoculum (1-20% v/v, especially 10% v/v of the microbial suspension from the previous stage of liquid culture, into fresh liquid medium.
For the reaction stage, a heavy inoculum (1-20% v/v, especially 10% v/v) of the microbial suspension, or of thawed cryopreserved cells are inoculated into fresh medium. The microorganisms are cultured at temperatures between about 20xc2x0 and 80xc2x0 C., preferably 25xc2x0 to 37xc2x0 C., and at pH from 4 to 9, especially between pH 5 and 8, depending on the specific microorganism used for the transformation. Incubating of the microorganisms was carried out over a time interval of 2-240 hours, preferably from 75 to 170 hours. The reaction was conducted aerobically, initially in parallel, multiwell reaction chambers, continuously supplied with air or enriched oxygen, and agitated. Subsequently, larger scale fermentations can be conducted in a similar manner in shaker flasks, and then in fermenters with stirring and aeration.
The addition of the starting material to the microbial culture is made between 0-72 hours of the inoculation of the reaction medium with prepared inocula, preferably after approximately 8-48 hours and especially after 24 hours of incubation. The addition of the starting material is most expediently carried out from a solution of an appropriate organic solvent, but can also be added as a solid powder, or as a suspension. From solution, the starting material is added most preferably in dimethylformamide (DMF), but also in ethanol, dimethyl sulfoxide (DMSO), dimethylacetamide (DMA), acetonitrile, tetrahydrofuran (THF) and, a formamide (i.e. dibutyl-, diisopropyl-, or diethyl-), a pyrrolidone (i.e. 1-methyl-, 1-ethyl-, 1-cyclohexyl-), 4-formyl-morpholine, 1-formylpiperidine, 1-formylpyrrolidine, tetramethyl-tetraethyl-, tetrabutylurea, a phosphine oxide (i.e. tripiperidino- or tripyrrolidino-), sulfolane, N-methyl-caprolactam, or mixtures thereof. Biocompatible organic solubilizers, such as cyclodextrins or surfactants (e.g., Tween 80 or Pluronic F38) can also be added to the reaction medium containing the microorganism.
The compounds of Formulae IA and/or IB can be isolated directly from the microbial broth or from clarified liquid after separation of the cells, for example, by centrifugation or filtration. These products can be isolated by extraction with organic solvents or by adsorption on hydrophobic resins or ion exchangers.
Additional variations of this invention may use the embodied microorganisms and standard techniques and conventional procedures for incubating the microorganisms and conducting the reactions, as disclosed in generally-available manuals. For instance, methods described in Demain, A. L. and J. E. Davies, Manual of Industrial Microbiology and Biotechnology, 2nd Ed. (1999) and Crueger, W. and A. Crueger, Biotechnology: A Textbook of Industrial Microbiology (1984) are applicable for preparing the cultures and carrying out the process of the present invention.
Of particular significance are compounds of the Formulae IIIA and/or IIIB: 
wherein R1, R2, R3, A, B, and D are defined above. Of these compounds, 4-(4-(4-hydroxydiphenyl)-1-piperidinyl)-1-hydroxybutyl)-xcex1,xcex1-dimethylpenylacetic acid is particularly preferred.
Another preferred class of compounds are the compounds of Formulae IVA and/or IVB: 
wherein R1, R2, R3, A, B, and D are defined above. Of these compounds, 4-[4-[4-diphenylmethoxy)-1-piperidinyl]-oxobutyl]-xcex1,xcex1dimethylphenylacetic acid is particularly preferred.
The present invention additionally relates to a process for the preparation of additional analogs of Formulae IA and/or IB starting from structures according to Formulae IIA and or IIB, with a microorganism according to the present invention.
Other illustrative examples of compounds prepared by the process of the present invention are as follows:
4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetic acid;
4-[4-[4-(diphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetic acid;
4-[4-[4-(diphenylmethylene)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetic acid;
4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-3-hydroxybenzeneacetic acid;
4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-2-hydroxybenzeneacetic acid;
4-[4-[4-(diphenylmethylene)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-3-hydroxybenzeneacetic acid;
4-[4-[4-(diphenylmethylene)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetic acid;
ethyl 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetate;
n-pentyl 4-[4-[4-(diphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetate;
ethyl 4-[4-[4-(diphenylmethylene)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetate;
methyl 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetate;
ethyl 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-(3-hydroxybenzene)acetate;
n-propyl 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-(2-hydroxybenzene)acetate;
n-hexyl 4-[4-[4-(diphenylmethylene)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-(3-hydroxybenzene)acetate;
ethyl 4-[4-[4-(diphenylmethylene)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetate;
4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetic acid;
4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-3-hydroxybenzeneacetic acid;
4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-2-hydroxybenzeneacetic acid;
4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-3-hydroxybenzeneacetic acid;
4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetic acid;
n-pentyl 4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetate;
ethyl 4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetate;
ethyl 4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-(3-hydroxybenzene)acetate;
n-propyl 4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-(2-hydroxybenzene)acetate;
n-hexyl 4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethyl-(3-hydroxybenzene)acetate; and
ethyl 4-[4-[4-(diphenylmethoxy)-1-piperidinyl]-1-hydroxybutyl]-xcex1,xcex1-dimethylbenzeneacetate.
The present invention additionally relates to a process for the preparation of additional analogs of Formulae IA and/or IB starting from structures according to Formulae IIA and or IIB, with a microorganism used according to the process (or an essentially equivalent process) embodied herein.
Particularly preferred are compounds of the formulae: 
Optionally, both diphenyl groups from the piperidine compound may be alkyl (e.g., methyl) substituted at the position para to the methylene, such as 
The compounds prepared by the methods of the present invention can be pharmaceutically acceptable salts in the form of inorganic or organic acid or base addition salts of the above compounds. Suitable inorganic acids are, for example, hydrochloric, hydrobromic, sulfuric, and phosphoric acids. Suitable organic acids include carboxylic acids, such as, acetic, propionic, glycolic, lactic, pyruvic, malonic, succinic, fumaric, malic, tartaric, citric, cyclamic, ascorbic, maleic, hydroxymaleic, dihydroxymaleic, benzoic, phenylacetic, 4-aminobenzoic, anthranilic, cinnamic, salicylic, 4-aminosalicylic, 2-phenoxybenzoic, 2-acetoxybenzoic, and mandelic acid. Sulfonic acids, such as, methanesulfonic, ethanesulfonic, and xcex2-hydroxyethane-sulfonic acid are also suitable acids. Non-toxic salts of the compounds of the above-identified formulae formed with inorganic and organic bases include, for example, those alkali metals, such as, sodium, potassium, and lithium, alkaline earth metals, for example, calcium and magnesium, light metals, for example, aluminum, organic amines, such as, primary, secondary, or tertiary amines, for example, cyclohexylamine, ethylamine, pyridine, methylaminoethanol, and piperazine. These salts are prepared by conventional means, for example, by treating the piperidine derivative compounds of Formulae IA and/or IB: 
where A, B, D, n, R1, R2, and R3 are defined above, with an appropriate acid or base.
The piperidine derivative compounds prepared by the methods of the present invention can be utilized as the biologically active components in pharmaceutical compositions. These compounds are useful as antihistamines, antiallergy agents, and bronchodilators. They may be administered alone or with suitable pharmaceutical carriers, and can be in solid or liquid form, such as, tablets, capsules, powders, solutions, suspensions, or emulsions.
The compounds prepared by the methods of this invention can be administered orally, parenterally, for example, subcutaneously, intravenously, intramuscularly, intraperitoneally, by intranasal instillation, or by application to mucous membranes, such as, that of the nose, throat, and bronchial tubes. Such application to mucous membranes can be achieved with an aerosol spray containing small particles of a compound of this invention in a spray or dry powder form.
The quantity of the compound administered will vary depending on the patient and the mode of administration and can be any effective amount. The quantity of the compound administered may vary over a wide range to provide in a unit dosage an effective amount of from about 0.01 to 20 mg/kg of body weight of the patient per day to achieve the desired effect. For example, the desired antihistamine, antiallergy, and bronchodilator effects can be obtained by consumption of a unit dosage form such as a tablet containing 1 to 50 mg of the compound of the present invention taken 1 to 4 times daily.
The solid unit dosage forms can be of the conventional type. This solid form can be a capsule, such as an ordinary gelatin type containing the compound of the present invention and a carrier, for example, lubricants and inert fillers such as, lactose, sucrose, or cornstarch. In another embodiment, these compounds are tableted with conventional tablet bases such as lactose, sucrose, or cornstarch in combination with binders like acacia, cornstarch, or gelatin, disintegrating agents such as, cornstarch, potato starch, or alginic acid, and a lubricant like stearic acid or magnesium stearate.
The compounds prepared according to the present invention may also be administered in injectable dosages by solution or suspension of the compounds of the present invention in a physiologically acceptable diluent with a pharmaceutical carrier. Such carriers include sterile liquids such as water and oils, with or without the addition of a surfactant and other pharmaceutically acceptable adjuvants. Illustrative oils are those of petroleum, animal, vegetable, or synthetic origin, for example, peanut oil, soybean oil, or mineral oil. In general, water, saline, aqueous dextrose and related sugar solution, and glycols such as, propylene glycol or polyethylene glycol, are preferred liquid carriers, particularly for injectable solutions.
For use as aerosols, the compounds in solution or suspension may be packaged in a pressurized aerosol container together with suitable propellants, for example, hydrocarbon propellants like propane, butane, or isobutane with conventional adjuvants. These compounds may be administered in a non-pressurized form, such as in a nebulizer or atomizer.
The compounds made according to the present invention can be used to treat warm blooded animals, birds, and mammals. Examples of such beings include humans, cats, dogs, horses, sheep, cows, pigs, lambs, rats, mice, and guinea pigs.
The following examples are illustrative of the invention embodied herein without being limiting in nature.